Coronal holes

A small recurrent coronal hole (CH190) in the
northern hemisphere could rotate to an Earth facing position on October 2.

Processed SOHO/EIT 284 image at 19:06 UTC on October 1. The
darkest areas on the solar disk are likely coronal holes.

Forecast

The geomagnetic field is expected to be quiet to active on October 2 and mostly quiet October 3-9.

Coronal holes (1)

Coronal mass ejections (2)

M and X class flares (3)

1) Effects from a coronal hole could reach Earth
within the next 5 days. When the high speed stream has arrived
the color changes to green.
2) Material from a CME is likely to impact Earth within 96 hours.
3) There is a possibility of either M or X class flares within the next
48 hours.

Propagation

Long distance low and medium frequency (below 2 MHz) propagation
along
east-west paths over high and upper middle latitudes is fair.
Propagation on long distance northeast-southwest paths is fair. Trans
Atlantic propagation conditions are normally monitored every night on
1470 kHz. Dominant station tonight: Radio Vibración (Venezuela). On other frequencies propagation varied quite a bit. At midnight
UTC North American stations were heard on about 50 frequencies with some of those (i.e. 1450 and 1490 kHz) having more than 1
station. Later on most of these signals disappeared, however, the often heard station last season on 610 kHz, WIOD Miami FL, was
heard for the first time this season. At 02h UTC and until 90 minutes before LSR stations from Colombia and Venezuela were strong
on quite a few frequencies with Mara Ritmo 900 (Venezuela) and 970 Radio Super (Colombia) good examples of the current conditions.
820 Radio Paradise was very strong at 04h UTC.

Data for all numbered solar regions according to the Solar Region
Summary provided by
NOAA/SEC. Comments are my own, as is the
STAR spot count (spots observed at or inside a few hours before
midnight) and data for regions not numbered by SEC or where SEC has
observed no spots.
SEC active region numbers in the table below and in the active region
map above are the historic
SEC/USAF numbers.

Active region

Date numbered

SEC
spot
count

STAR
spot
count

Location at midnight

Area

Classification

Comment

10812

2005.09.23

S03W33

plage

S595

2005.09.30

N12W28

plage

Total spot count:

0

0

SSN:

0

0

Monthly solar cycle data

Month

Average solar
flux at Earth

International sunspot number

Smoothed sunspot number

2000.04

184.2

125.5

120.8
cycle 23 sunspot max.

2000.07

202.3

170.1

119.8

2001.12

235.1

132.2

114.6 (-0.9)

2004.08

109.6

40.9

39.2 (-1.0)

2004.09

103.1

27.7

37.5 (-1.7)

2004.10

105.9

48.0

35.9 (-1.6)

2004.11

113.2

43.5

35.3 (-0.6)

2004.12

94.5

17.9

35.2 (-0.1)

2005.01

102.2

31.3

34.6 (-0.6)

2005.02

97.2

29.2

33.9 (-0.7)

2005.03

89.9

24.5

33.5 (-0.4)

2005.04

86.0

24.4

(31.9 predicted, -1.6)

2005.05

99.3

42.6

(29.4 predicted, -2.5)

2005.06

93.7

39.6

(28.1 predicted, -1.3)

2005.07

96.4

39.9

(26.9 predicted, -1.2)

2005.08

90.5

36.4

(25.0 predicted, -1.9)

2005.09

91.1

22.1

(23.0 predicted, -2.0)

2005.10

72.1 (1)

0.0 (2)

(21.0 predicted, -2.0)

1) Running average based on the daily 20:00 UTC observed solar flux
value at 2800 MHz.
2) Unofficial, accumulated value based on the Boulder (NOAA/SEC)
sunspot number. The official international sunspot number is typically
30-50% lower.

This report has been prepared by Jan
Alvestad. It is based partly on my own observations and analysis,
and
partly on data from some of these solar data sources.
All time references are to the UTC day. Comments and suggestions are
always welcome.